Optical properties database
If you use material type 99 in your MEDIUM_VECTOR file, data are automatically loaded from optical properties database and used as tabulated values or PLRC data, according to their definition in the database. The only parameter of the material type is therefore an unique material identifier in the optical properties database (automatically installed with GSvit and located e.g. in /share/gsvit/data/spectra/ - exact locaton depends on way how and on which OS you install GSvit).
If there are more models available, you need to choose the identifier correctly. You can use for example identifiers Ag, Ag_drude and Ag_cp for silver, where the first identifier (Ag) means tabulated optical properties (which for most of the metals won't work at visible wavelengths) and the next identifiers make choice of an dispersive model for metal treatment.
Absolute majority of the data were acquired from SOPRA database or from Refractiveindex.info web pages. This also means that absolute majority of data are tabulated, which is good for running single frequency FDTD calculation, but not good for multiple frequencies within a single FDTD run. To treat multiple frequencies in a single FDTD run, a dispersive model needs to be used (which is still in preparation).
If tabulated data from database are used, the automatically detected or user prescribed central source wavelength is used to pick (interpolate) the right values of optical parameters from the database. If the automatically detected or prescribed wavelength range does not fit the spectrum, a warning is issued and closest value is used. Note that this typically means that completely wrong value is used as the optical properties are strongly wavelength-dependent.
Adding your own spectra
Optical properties are loaded from a file, based on its name. Adding more files to the appropriate directory (e.g. in /share/gsvit/data/spectra/ - exact location depends on way how and on which OS you install GSvit) is the simplest way how to extend GSvit capabilities (sending us the file to share it with other users is even a better option).
File for defining the optical properties is a plain text file, consisting of the following fields:
Parameter "type" can be as follows:
Data for different formulas are listed in order of its appearance in the formula. For tabulated data, the values are preceded by their total number. Tabulated data are interpolated when necessary.
Example of a tabulated spectrum (note that wavelength can be in other powers in meter (here nanometers), it is corrected according to range (second line of the file):
nk 0.163138 2.06642 SOPRA N&K Database 71 163 1.5 0.1 ...
List of available optical data
Here follows a list of all the optical properties files available in GSvit installation (25/01/2012). Absolute majority of data comes from SOPRA NK database, references for data source are given in each file separaterly. Filenames should be self-explanatory, in case of doubts see the appropriate file for description of data origin and used model:
Ag Ag_cp Ag_cp3 Ag_drude Al Al2O3 Al2O3_Palik AlAs AlCu AlGaAs_0Al AlGaAs_10Al AlGaAs_20Al AlGaAs_30Al AlGaAs_40Al AlGaAs_50Al AlGaAs_60Al AlGaAs_70Al AlGaAs_80Al AlGaAs_90Al AlGaAs_100Al AlGaInP_0Al AlGaInP_10Al AlGaInP_30Al AlGaInP_60Al AlGaInP_70Al AlGaInP_100Al AlON AlSb AlSi AlSiTi aSi a-Si Au BaF2 BK7 CaF2 Carbon CCl4 CdSe CdTe CO CO2 CoSi2 Cr Cr3Si Cr5Si3 CrSi2El2 Cu Cu2O CuO Diamond ethanol FeSi2_1 FeSi2_2 FeSi2_3 GaAs GaAsO GaP GaP_100 GaPO GaSb GaSbO Ge Ge_100 HfO2 HfSi2 HgCdTe_0Te HgCdTe_20Te HgCdTe_30Te ice InAs InAsO InGaAs InGaSb_0Ga InGaSb_10Ga InGaSb_30Ga InGaSb_50Ga InGaSb_70Ga InGaSb_90Ga InGaSb_100Ga InP InPO InSb INSbO Ir Ir3Si5_1 Ir3Si5_2 ITO KCl LASF9 Li LiF methanol MgF2 MO MoSi2_extraordinary MoSi2_ordinary NbSi_a NbSi_b Ni Ni2Si Ni3Si NiSi PbS PbSe PC Pd Pd2Si_extraordinary Pd2Si_ordinary PMMA Pt ReSi SF11 Si_100 Si_110 Si_111 Si11Ge89 Si20Ge80 Si28Ge72 Si3N4 Si65Ge35 Si85Ge15 Si98Ge02 SiC SiCr SiGe_Ge SiGe_Si SiO SiO2 Ta TaO_1 TaO_2 Te ThF4 Ti TiNi TiO2 TiSi V VSi2_a VSi2_b W water WSi2_a WSi2_b Y2O3 ZnS ZnSe ZnSeTe_0Te ZnSeTe_10Te ZnSeTe_30Te ZnSeTe_50Te ZnSeTe_70Te ZnSeTe_90Te ZnSeTe_100Te ZrO2 ZrSi2
(c) Petr Klapetek, 2013